Unit 3 (Hind limb vas/nerves and head/nervous system) Flashcards Preview

Anatomy I (Fall) > Unit 3 (Hind limb vas/nerves and head/nervous system) > Flashcards

Flashcards in Unit 3 (Hind limb vas/nerves and head/nervous system) Deck (497):
1

Where does the external iliac artery arise from the aorta?

Level of the 6th or 7th lumbar vertebrae.

2

Vascular lacuna

The point at which the external iliac crosses the abdominal wall and becomes the femoral artery (medial circumflex femoral a. also passes here)
Located in the aponeurosis of the external abdominal oblique (also called the inguinal ligament).

3

Caudal gluteal artery

Larger of two terminal branches of the internal iliac a. (other is internal pudendal)
Gives off cranial gluteal artery and iliolumbar artery.

4

Cranial gluteal artery

From the caudal gluteal artery.
Supplies the middle and deep gluteal mm.

5

Iliolumbar artery

From the caudal gluteal artery.
Supplies the psoas major, iliopsoas, sartorius, tensor fasciae latae, and middle gluteal mm.

6

Deep femoral

Only branch of the external iliac
To the pudendoepigastic trunk and the medial circumflex femoral a.

7

Pudendoepigastric trunk

Gives rise to the caudal epigastric artery and the the external pudendal artery.

8

Caudal epigastric artery

Branch of the deep femoral
Supplies the ventral surface of the abdominal wall.
Mainly rectus abdominis and oblique, transversus abdominalis.

9

External pudendal artery

Passes through the inguinal canal and supplies the external prepuce.

10

What muscles bound the femoral triangle?

Sartorius
Vastus medialis/rectus femoris
Pectineus/adductor

11

Medial circumflex femoral artery

Continuation of the deep femoral and leaves the abdomen in the vascular lacuna.
Deep branch
Transverse branch

12

Deep branch of the medial circumflex femoral a.

Smaller of the two branches.
Supplies adductor and vastus medialis mm.

13

Transverse branch of the medial circumflex femoral a.

Larger of the two branches.
Supplies semimembranosus m.

14

Femoral artery

Continuation of the external iliac a.
Branches:
Superficial circumflex iliac a.
Lateral circumflex femoral a.
Proximal caudal femoral a.
Saphenous a.
Descending genicular a.
Middle caudal femoral a.
Distal caudal femoral a.
Terminates in the popliteal artery.

15

Superficial circumflex iliac. a.

Supplies sartorius, tensor fasciae latae, and the rectus femoris.

16

Lateral circumflex iliac a.

Supplies all four head of the quadriceps, tensor fasciae latae, superficial and middle gluteals, and the hip joint.

17

Proximal caudal femoral a.

Supplies pectineus, adductor, and gracilis.

18

Saphenous a.

Medial side of the leg only.
Supplies the skin on the medial side of the stifle.
Terminates in a cranial and caudal branch.

19

Descending genicular a.

Supplies the medial stifle
Arises at approximately the same level of the saphenous and the middle caudal femoral a.

20

Middle caudal femoral a.

Supplies adductor and semimembranosus mm.

21

Distal caudal femoral a.

Supplies biceps femoris, semimembranosus, semitendinosus, gastrocnemius, and the digital flexors.

22

Popliteal a.

Termination of the femoral a.
Supplies the stifle, gastrocnemius, and popliteus mm.
Terminates as the cranial and caudal tibial aa.

23

Lateral saphenous vein

Not paired with an artery
Used for venipuncture in the dog.
Terminates in the distal caudal femoral vein .

24

Cranial branch of the saphenous artery.

Supplies flexor surface of the tarsus and terminates in the dorsal common digital arteries.

25

Caudal branch of the saphenous artery

Supplies tarsus and the deep structures of the metatarsus. Terminates in the deep plantar arch supplying the plantar metatarsals.

26

Cranial tibial artery

Underneath the cranial tibial m.
Supplies the fibulas longus, the long digital extensor, and cranial tibial mm.

27

Lumbosacral plexus

Diffuse and consists of the ventral branches of lumbar and sacral spinal nerves (mainly somatic nerves)
Nerves L1 - S3 can contribute
L1-L3 innervate mainly abdominal wall
L4-S3 innervate the hindlimb.

28

Obturator nerve

Runs through the obturator sulcus of the obturator foramen.
Innervates: adductor muscles of the limb (external obturator, pectineus, gracilis, and the adductor).

29

Femoral nerve

Emerges from the iliopsoas muscle and follows the femoral a.
Supplies iliopsoas and the quadriceps mm.

30

Saphenous nerve

Branches off the femoral nerve inside the ilopsoas. Innervates the sartorius, medial side of the leg and paw.

31

Cranial gluteal nerve

Branch from the lumbosacral trunk.
Runs with the cranial gluteal artery to innervate the tensor fasciae late, middle, and deep gluteal mm.

32

Caudal gluteal nerve

Branch from the lumbosacral trunk.
Runs with the caudal gluteal artery to innervate the superficial gluteal m.

33

Pudendal nerve

In the ischiorectal fossa
Branches:
Caudal rectal n.
Perineal nn.
Dorsal nerve of the penis/clitoris

34

Caudal cutaneous femoral nerve

Runs just superficially to the pudendal nerve.

35

Caudal rectal nerve

Innervates the external anal sphincter

36

Perineal nerves

Innervates the skin of the anus, perineum, muscles of the penis, vestibule, and vulva, and the scrotum or labia. Multiple heading caudally from the pudendal nerve.

37

Dorsal nerve of the penis

Medial nerve off the pudendal nerve.
Sensory to skin of the glans

38

Dorsal nerve of the clitoris

Medial nerve off the pudendal nerve.
Sensory to the clitoris.

39

Lumbosacral trunk

Origin of the sciatic, caudal gluteal, and cranial gluteal nerves near the ischiatic notch.
From the 6th/7th lumbar spinal nerves.

40

Sciatic nerve

Branch from the lumbosacral trunk.
Innervates the biceps femoris, semitendinosus, semimembranosus, internal obturator, gemelli, and quadratus femoris mm. with small branches as it passes.
Terminates in the common fibular and tibial nerves.

41

What is another name for the common fibular nerve?

Common peroneal nerve.

42

Common fibular nerve

Smaller branch of the sciatic
Deep and superficial branches
Eventually forms common digital nerves that innervate the paw.

43

Superficial fibular nerve

Caudal branch off the common.

44

Deep fibular nerve

Cranial branch off the common.
Innervates the cranial tibial, long digital extensor, and fibularus longus.

45

Dorsal pedal artery

Branch off of the cranial tibial artery.
Supplies the tarsus and terminates at the arcuate artery at the tarsometatarsal joint.

46

Arcuate artery

Gives off dorsal metatarsal arteries and runs through the ligaments of the foot to the plantar side.

47

Perforating branch of the arcuate artery

Branch that supplies the plantar side of the paw.

48

Tibial nerve

Larger branch of the sciatic nerve.
Passes between the two heads of the gastrocnemius m.
Supplies the extensors of the tarsus/flexors of digits, the gastrocnemius, the stifle, the popliteus, the superficial digital flexor, and both digital deep flexor mm.
Terminates in the medial and lateral plantar nerves.

49

Tarsal tunnel

Formed by the space between the sustentaculum tali, calcanean tuber, and flexor retinaculum.
Contains the tendon of the lateral digital flexor and its synovial sheath, medial and lateral plantar nerves, and the caudal branch of the saphenous a.

50

Medial and lateral plantar nerves

Off the tibial nerve, main innervation to the plantar surface of the hind paw.

51

Skull

Both bony and cartilaginous elements.

52

Cranium

Elements of the skull that surround the brain.

53

Calvaria

Elements of the skull that make up the roof (usually referred to as the dorsal cranium).

54

Parietal bone

Backmost bone of the dorsal skull.

55

Frontal bone

Middle bone of the dorsal skull between the zygomatic arches.

56

External sagittal crest

Formed on the midline of the skull by the parietal and interparietal bones.
Joins with the nuchal crest at the external occipital protuberance.
Lacking in bracheocephalic dog.

57

Interparietal bone

Unpaired bone
Appears to be a bony process off of the occipital bone (fuses prenatally), running between the median fusion of the parietal bone.

58

Temporal lines

Replaces the external sagittal crest in bracheocephalic dogs, running sagittally to the sagittal crest.
Meet the nuchal crest at two individual external occipital protuberances.

59

Nuchal crest

Transverse ridge that marks the transition between the caudal and dorsal surfaces of the skull.

60

Temporal bones

Lateral to the parietal bone.
Made up of:
Squamous part (Zygomatic process)
Tympanic part (tympanic bulla)
Petrous part (inner ear labyrinths, promontory, mastoid process)

61

Basisphenoid

Forms the middle of the ventral part of the cranium between the occipital and pre sphenoid parts.
Two wings on the lateral side of the skull, bear the alar canal.

62

Presphenoid

Forms a small medial spine on the ventral part of the cranium rostral to the basisphenoid bone.
Small wing on the lateral side of the skull that bears the optic foramen.

63

Nasal bone

Rostral dorsal bone. Paired.

64

Maxilla

rostral lateral bone bearing the cheek teeth. Part of the dorsum of the skull and the hard palate.

65

Incisive bone

Most rostral tip of the skull, ventral and dorsal. Bears the upper incisors.
Long nasal process to articulate with the maxilla.

66

Nasal aperture

Opening of the two nostrils between the nasal and incisive bones. More round in brachiocephalic breeds.

67

Orbit

Cavity in which the eye is situated, continuous with the zygomatic arch in the skull. Surrounded by orbital margin, orbital ligament, zygomatic salivary gland, pterygoid muscle, and temporal muscle.

68

Orbital margin

Bony part of the orbit
Formed by:
Maxillary bone
Frontal bone
Lacrimal bone
Zygomatic bone

69

Orbital ligament

Closes the orbit in life
Superficial to the lacrimal gland.

70

Zygomatic arch

Formed by:
Zygomatic process of the maxilla
Zygomatic bone
Zygomatic process of the temporal bone
Origin of the masseter muscle

71

Pterygopalatine fossa

Located ventral to the orbit
Formed by the maxilla, palatine bone, and the zygomatic bone.

72

Optic canal

Passes through the presphenoid bone.
Bears: optic nerve

73

Orbital fissure

Formed by the articulation between the basisphenoid and presphenoid bones
Bears: oculomotor, trochlear, abducent, and ophthalmic nerves plus some vessels.

74

Rostral alar foramen

Passes through the basisphenoid bone
Rostral entrance into the alar canal
Bears: maxillary artery and maxillary nerve

75

Temporal fossa

Convex space on the parietal and temporal bones that is bounded by the sagittal line, nuchal crest, and the zygomatic process.

76

Caudal palatine foramen

Ventral foramen on the rostral part of the pterygopalantine fossa.
Bears the major palatine artery, vein, and nerve moving into the palatine canal to the hard palate.

77

Sphenopalatine foramen

Dorsal foramen on the rostral part of the pterygopalantine fossa.
Bears the sphenopalatine artery and vein and the caudal nasal nerve into the nasal cavity.

78

Maxillary foramen

Caudal opening of the infraorbital canal, found in the rostral portion of the zygomatic arch.
Bears the infraorbital artery, vein, and nerve

79

Alveolar canals

Found around the maxillary foramen for small nerves to the molars.

80

Fossa for the lacrimal sac

Dorsal to the maxillary foramen in the ventral part of the orbit.
Continues into the nasolacrimal canal.

81

Infraorbital foramen

Rostral opening of the infraorbital canal.
Dorsal to the 3rd premolar tooth.

82

Alveolar juga

Lateral elevations of the maxilla bone to allow space for the roots of the cheek teeth.

83

Paracondylar process

Ventral projection of the occipital bone lateral to the occipital condyles.
Articulates with the lateral part of the tympanic bulla.
Origin of the digastricus muscle.

84

Occipital bone

Forms the caudal part of the skull
Four parts from prenatal bone fusion
Basiocciptal bone
Paired exoccipitals (bear the condyles)
Supraoccipital bone

85

Tympanic bulla

Encloses the middle ear cavity and its ossicles.

86

Ear ossicles

Incus, Stapes, and Malleus

87

External acoustic meatus

Open portion on the lateral side of the tympanic bulla through which the promontory can be seen. Covered by tympanic membrane in life which is then surrounded by the annular cartilage of the external ear around the periphery.

88

Promontory

Barral shaped eminence on the ventral surface of the tympanic bulla.
Contains the vestibular and cochlear windows.

89

Cochlear window

End of the "barrel" of the promontory.
Closed in life by a membrane.

90

Vestibular window

On the dorsal side of the "barrel" of the promontory.
Contains the footplate of the stapes

91

Incus

One of three ear ossicles

92

Malleus

One of three ear ossicles

93

Stapes

One of three ear ossicles

94

Mastoid process

Only external part of the petrosal part of the temporal bone. Lies lateral to the paracondylar process.

95

Oval foramen

Entrance from the cranial cavity to the lateral side of the skull.
Bears the mandibular nerve from the trigeminal nerve.

96

Foramen lacerum

Rostromedial edge of the tympanic bulla.
Bears a loop of the internal carotid artery that courses rostrally through the carotid canal and entered the cavernous sinus on the floor of the cranial cavity.

97

Musculotubal canal

Lateral to the foramen lacerum and less visible.
Bears the auditory tube that connects the oral and nasal cavities

98

Tympano-occiptial fissure

Opening between the occipital bone and the tympanic part of the temporal bone.
Two parts: petro-occipital canal (ventral petrosal venous sinus) and carotid canal (internal carotid artery)

99

Hypoglossal canal

Caudomedial to the tympano-occiptal fissure
Bears the hypoglossal nerve

100

Caudal alar foramen

Caudal opening of the alar canal in the basisphenoid bone.

101

Round foramen

Opening from the cranial cavity into the alar canal. Bears the maxillary nerve from the trigeminal nerve. This will exit from the rostral alar foramen. 1

102

Mandibular fossa

Depression for articulation of the condylar process of the mandible on the zygomatic process of the temporal bone.

103

Retroarticular process

Caudal wall of the medial aspect of the mandibular fossa

104

Retroarticular foramen

Caudal to the retroarticular process
Bears the emissary vein

105

Stylomastoid foramen

Between the tympanic bulla and the mastoid process.
Bears the facial nerve

106

Interalveolar septae

Separate the alveoli of adjacent teeth

107

Interradicular septae

Separate the alveoli of teeth with multiple roots

108

Hard palate

Formed from the ventral horizontal parts of the incisive, maxilla, and palatine bones.

109

Palatine fissure

Two large holes in the incisive bone near the incisors.

110

Major palatine foramen

Medial to the fourth cheek tooth.
Bears branches of the major palatine artery, vein, and nerve.

111

Minor palatine foramina

Caudal to the major palatine foramen.
Bears branches of the major palatine artery, vein, and nerve.

112

Choanae

Openings of the right and left nasal cavities into the nasopharynx. Located at the caudal end of the hard palate where the vomer articulates with the palatine bones.

113

Basioccipital bone

Base of the caudal part of the foramen magnum and caudal part of the ventral surface of the cranium.

114

Foramen magnum

Large foramen that bears the medulla of the brain stem (continues as the spinal cord) and is surrounded by the occipital condyles.

115

Mandible

Compose the inferior jaw.
Join at the intermandibular articulation.
Has a body and ramus.

116

Body of the mandible

Horizontal part of the mandible.

117

Ramus of the mandible

Vertical part of the mandible.

118

Alveolar border of the mandible

Dorsal part of the mandible that bears the alveoli of the inferior teeth.

119

Masseteric fossa

Triangular fossa on the lateral side of the mandibular ramus.
Insertion for the masseter muscle.

120

Coronoid process of the mandible

Most dorsal part of the mandibular ramus.

121

Mandibular foramen

Caudal opening of the mandibular canal on the medial side of the mandible.

122

Mandibular canal

Bears the inferior alveolar artery and vein and inferior alveolar nerve

123

Mental foramina

Usually three, the rostral openings of the mandibular canal.
Allows the inferior alveolar nerve to innervate the chin and lower lip.

124

Condylar process of the mandible

Middle part of the mandibular ramus that articulates with the mandibular fossa as the temporomandibular joint.

125

Temporomandibular joint

Between the condylar process of the mandible and the mandibular fossa of the temporal bone.

126

Mandibular notch

Between the coronoid and condylar processes. U-shaped depression.
Bear the motor branches of the mandibular nerve that innervate the masseter muscle.

127

Angular process of the mandible

Most ventral part of the mandibular ramus.
Insertion for the temporal muscle.
Hooked in the dog.
Insertion of the pterygoid muscle on the medial side.

128

Bones of the hyoid apparatus

Tympanohyoid cartilage
Stylohyoid
Epihyoid
Ceratohyoid
Basihyoid
Thyrohyoid

129

What is the molar/premolar status of the inferior and superior carnassials?

Superior = last premolar
Inferior = first molar

130

Parts of the tooth

Crown, root, and neck

131

Cheek teeth

Molars and premolars

132

Dental formula of the adult dog

I 3/3
C 1/1
P 4/4
M 2/3
Total = 42 with 10/11
All = half, left or right

133

Dental formula of the young dog with milk teeth

I 3/3
C 1/1
P 3/3
Totatl = 28 with 7/7

134

Premolar carrying space

Between the premolars when the mouth is closed.

135

Surfaces of the teeth

Vestibular surface = lateral tooth surface
Lingual surface = inferior medial tooth surface
Palantine surface = superior medial tooth surface
Mesial contact surface: rostral side of the tooth
Distal surface: caudal side of the tooth
Occlusal/masticating suface: top of the tooth

136

Cribriform plate

Caudal wall of the ethmoid bone, rostral boundary of the cranial cavity.
Transmit blood vessels to the brain and olfactory nerves to the olfactory bulbs.
Holes = olfactory foramina

137

Rostral cranial fossa

Rostral to the optic canal.
Contains the olfactory bulbs of the brain and the rostral part of the frontal lobes.

138

Middle cranial fossa

Between the optic canal and the petrosal crest.
Contains most of the paired foramina of the cranial cavity. Rostral to caudal is:
Optic canal
Orbital fissure
Round foramen
Oval foramen
Contains the parietal and temporal lobes of the cerebrum.

139

Caudal cranial fossa

Between the petrosal crest and the foramen magnum.
Contains the cerebellum, the pons, and the medulla.

140

Ethmoid bone

Cribriform plate and the attached ethmoid labyrinth as well as the bony portion of the nasal septum and the orbital laminae.

141

Sella turcica

"Turkish saddle" composed of the hypophyseal fossa and the dorsum sellae.

142

Hypophyseal fossa

Small depression rostral to the dorsum sellae that contains the pituitary gland.

143

Dorsum sellae

Unpaired quadrilateral process in the middle cranial fossa.

144

Canal for the trigeminal nerve

In the tip of the petrosal process of the temporal bone
Trigeminal nerve will pass through this before breaking into three parts to pass through the foramina in the middle cranial fossa.

145

Internal acoustic meatus

Caudal to the canal for the trigeminal nerve
Contains the facial and vestibulocochlear nerve

146

Cerebellar fossa

Dorsocaudal to the internal acoustic meatus
Contains a small lateral portion of the cerebellum.

147

Jugular foramen

Between the petrosal temporal and the occipital bones inside the cranial cavity
Opens to the tympano-occipital fissure.
Contains the glossopharyngeal, vagus, and accessory cranial nerves and the sigmoid venous sinus.

148

Hypoglossal canal

Contains the hypoglossal nerve
Caudal to the jugular foramen and medial to the condyloid canal.

149

Tentorium osseum

Rostroventral projection of the caudal wall of the cranial cavity and bears the tentorium cerebelli.

150

Tentorium cerebelli

Connection of dural membrane between the petrosal processes and the tantrum osseum.
Separates the cerebrum from the cerebellum

151

Nasopharynx

Cavity just rostral to the chonae

152

Conchae

Turbinates, bony scrolls inside the nasal cavity. In life are covered by epithelium.

153

Dorsal nasal concha

Most dorsal scroll off of the cribriform plate. Extends as the shelf attached along the medial surface of the nasal bone.

154

Ventral nasal concha

Attach to a crest on the medal surface of the maxilla. In the middle of the nasal cavity but never contacts the median nasal septum.

155

Ethmoidal labyrinth

Attached to the cribriform plate. Very delicate and compose the fundus of the nasal cavity.

156

Ectoturbinates

Extension of the ethmoidal labyrinth into the rostral portion of the frontal sinus

157

Endoturbinates

Extension of the ethmoidal labyrinth to the vomer (which separates the labyrinth from the nasopharynx) and the presphenoid.

158

Nasal septum

Separates the right and left nasal cavities. Septal cartilage in the rostral 2/3, osseous part formed by the perpendicular plate of the ethmoid bone, septal processes of the frontal and nasal bones, and the sagittal potion of the vomer.

159

Septal cartilage

The cartilaginous portion of the nasal septum in the rostral 2/3. Articulates with cartilage at the nares that prevent collapse of the nostrils. Ventrally, fits into a groove formed by the vomer.

160

Dorsal nasal meatus

One of four passages through the concha. Between the nasal bone and the dorsal nasal concha.

161

Middle nasal meatus

One of four passages through the concha. Between the dorsal nasal concha and the ventral nasal concha.

162

Ventral nasal meatus

One of four passages through the concha. Between the ventral nasal concha and the hard palate.

163

Common nasal meatus

One of four passages through the concha. Vertical space on each side of the nasal septum where a nasal feeding tube may be passed.

164

Lateral frontal sinus

Largest of the sinuses and the only that has clinical relevance.
Occupies the zygomatic process and then extends caudally. Often has partial bony separations. Reaches from midline to the temporal line.

165

Rostral frontal sinus

Small between the median plane and the orbit.

166

Medial frontal sinus

Small between the median plane, rostral frontal sinus, and lateral frontal sinus.

167

Maxillary recess

Communicates with the nasal cavity with an opening through the rostral roots of the fourth superior premolar (carnassial). Continues caudally to the last molar tooth.

168

Lateral nasal gland

Occupies the rostral part of the maxillary recess. Duct opens into the dorsal vestibule. Secretions to prevent desiccation caused by nasal panting.

169

Articular disc of the temporomandibular joint

Thin cartilagenous disc that separates the articular surfaces of the temporal bone and mandible. Divides the joint capsule into two compartments.

170

Philtrum

The median grew separating the right and left parts of the superior lip. Incorrect fusion can cause a cleft lip here in fetal development.

171

Vestibule

The space in between the lips and the teeth/gums

172

Platysma

Attachments: dorsal median raphe of the neck and angle of the mouth.
Radiates into the orbicularis oris.
"Smiling" or panting muscle

173

Orbicularis oris

Extends from one lip to the other around the angle of the mouth.
Connects at the median plane in the incisor region at the median plane of each jaw.

174

Buccinator muscle

Thin wide muscle that forms the foundation of each cheek.
Attachments: alveolar margins of the mandible and maxilla and the buccal mucosa.

175

Other name for lips

Inferior and superior labia oris

176

Other name for cheeks

Buccae

177

Levator nasolabialis

Flat muscle attaching to the maxillary bone and edge of superior lip and nares.
Action: dilates the nostril and raises the superior lip.

178

Superior and inferior palpebrae

Top and bottom eyelids

179

Palpebral fissure

Gap between the eyelids

180

Medial and lateral palpebral commissures

Joining of the eyelids on either side of the palpebral fissure. Each attached by ligaments to the adjacent bone.

181

Medial and lateral palpebral ligaments

Attach the medial and lateral palpebral commissures to the adjacent bone. Medial is well developed and attaches to the frontal bone. Lateral is poorly developed and attaches to the zygomatic bone.

182

Palpebral conjunctiva

Mucous membrane on the inner surface of the eyelid.

183

Bulbar conjunctiva

Mucous membrane continuous with the palpebral conjunctiva on the globe of the eye

184

Fornix

Pocket formed between the bulbar and palpebral conjunctiva.

185

Conjunctival sac

Potential cavity formed by the fornix between the palpebral and bulbar conjunctiva

186

Lacrimal caruncle

Triangular prominence of finely furred skin at the medial commissure of the eye.

187

Lacrimal punctum

Beginning of the dorsal and ventral lacrimal ducts, a few millimeters from the medial commissure.

188

Lacrimal gland

Located ventral to the zygomatic process.
Secretes serous fluid through duct openings into the dorsolateral part of the conjunctival sac.
Goblet cells and tarsal glands also aid in forming tear secretion.

189

Lacrimal canaliculi

Collection of serous fluid from the lacrimal gland after it has passed over the cornea and was collected by the lacrimal puncta.

190

Lacrimal sac

Collection of the serous fluid from the lacrimal canaliculi.

191

Nasolacrimal duct

Moves the fluid from the lacrimal sac to the ventral nasal meatus where evaporation takes place.
Opens on the ventral aspect of the alar fold in the nose.

192

Plica semilunaris

Third eyelid
Concave fold of palpebral conjunctiva and cartilage protruding from the medial angle of the eye.
Surrounding by the superficial gland of the third eyelid and some lymphoid tissue.

193

Superficial gland of the third eyelid

Fat and glandular tissue surrounding the cartilage in the plica semilunaris. Secretes serous solution.

194

Orbicularis oculi

Lies in the eyelids.
Attached medially to the medial palpebral ligament.

195

Retractor anguli oculi lateralis

Covers the lateral palpebral ligament.
Closes the palpebral fissure

196

Levator palpebrae superioris

Arises deep within the orbit
Elevates the superior lid.

197

Rostral auricular muscles

Lie on the forehead caudal to the orbit and converge towards the auricular cartilage. Meet on the midline.

198

Scutiform cartilage

Boot-shaped cartilagenous plate in the muscles rostral and medial to the external ear. Isolated.

199

Caudal auricular muscles

Arise from the median raphe of the neck and attach directly to the auricular cartilage.

200

Oral cavity

Divided into the vestibule and the oral cavity proper.

201

Ducts of the zygomatic gland

Open into the vestibule lateral ago the last superior molar

202

Palatoglossal arch

Fold of tissue that extends from the body of the tongue to the beginning of the soft palate.

203

Mimetic muscles

Muscles of facial expression - many small superficial muscles of the face all innervated by the facial nerve.

204

Parts of the tongue

Root (caudal third)
Body (rostral to the body but still connected by the frenulum)
Apex (free extremity)

205

Filiform papillae

Found on the body and apex of the tongue
Tips directed caudally

206

Conical papillae

Replace the filiform papillae at the root of the tongue - one pointed tip.

207

Fungiform papillae

Smooth, rounded surfaces, fewer in number within both the filiform and conical papillae. Taste buds.

208

Foliate papillae

Lateral margins of the root of the tongue rostral to the palatoglossal arch. Taste buds.

209

Vallate papillae

Located at the junction of the body and root of the tongue.
4-6 in the dog arranged in the form of a V with apex directed caudally. Taste buds.

210

Lingual frenulum

Ventral fold of mucosa that attaches the tongue to the floor of the oral cavity.

211

Sublingual caruncle

Slightly raised part of the mucosa lateral to the rostral part of the frenulum and protrudes from the floor of the oral cavity.

212

Sublingual fold

Extends caudally from the caruncle.

213

Mandibular duct

Found in the sublingual fold.
Separate or common opening with the mandibular duct on the sublingual caruncle.

214

Major sublingual duct

Found in the sublingual fold. Separate or common opening with the mandibular duct on the sublingual caruncle.

215

Lyssa

Fusiform fibrous spicule that lies in the ventral part of the apex of the tongue.

216

Mandibular salivary gland

Large round gland on the side of the head between the maxillary and linguofacial veins. Covered by a thick capsule.

217

Sublingual gland

Caudal also included in the capsule of the mandibular salivary gland.

218

Parotid salivary gland

Lies between the mandibular gland and the ear. Roughly V-shaped.

219

Parotid lymph node

Small lymph node rostral to the parotid salivary gland.

220

Parotid duct

Formed by 2-3 covering radicles leaving the rostral border of the gland.
Runs across the masseter, leaving a groove on the muscle. Opens into the vestibule on a small papilla at the level of the caudal margin of the superior carnassial.

221

Zygomatic salivary gland

Medial to the zygomatic bone between the eyeball and the pterygoid muscle.

222

Incisive papilla

Small eminence located just caudal to the central incisor teeth.

223

Incisive duct

Fissure on either side of the incisive papilla that opens into the ventral nasal meatus.

224

Vomeronasal organ

Extends caudally from the incisive duct. Olfactory receptor for sexual stimuli or kin recognition. Very small and on the sagittal plane - does not exceed 1 mm thick and 2-3 cm long.

225

Oropharynx

Extends from the palatoglossal arches to the caudal border of the soft palate. Contains the palatine tonsil.

226

Palatine tonsil

Located caudal to the palatoglossal arches. Attached laterally to the palatine fossa.

227

Semilunar fold

Medial wall of the palatine fossa that folds over the palatine tonsil.

228

Nasopharynx

Extends from the chonae to the caudal end of the soft palate.

229

Palatopharyngeal arch

Folds that extend from the caudal end of the soft palate to the dorsolateral wall of the nasopharynx. Marks the end of the nasopharynx.

230

Auditory tube

Slitlike opening in the lateral wall of the nasopharynx dorsal to the soft palate.

231

Laryngopharynx

Dorsal to the larynx. From the palatopharyngeal arches to the beginning of the esophagus. Not a clear distinction between the oropharynx and the laryngopharyx.

232

Pharyngoesophageal limen

Annular constriction of soft tissue at the level of the cricoid cartilage, marking the beginning of the esophagus.

233

Pharyngeal muscles (8)

Cricopharyngeus
Thyropharyngeus
Hyopharyngeus
Palatopharyngeus
Pteryopharyngeus
Stylopharyngeus
Levator veli palatini
Tensor veli palatini

234

Cartilages of the larynx

Epiglottic
Thyroid
Artenoid
Cricoid

235

Epiglottic cartilage

Unpaired. Most cranial of the laryngeal cartilages.
Lingual surface attached to the basihyoid bone.
Lateral margin attached by mucosa to the cuneiform process of the arytenoid process.
Attaches to the body of the thyroid process caudally.

236

Epiglottic fold

Formed from the mucosa between the the cuneiform process of the arytenoid cartilage to the lateral margin of the epiglottic cartilage.

237

Thyroid cartilage

Unpaired. Deep trough that surrounds the ventrolateral aspects of the other cartilages cranially.

238

Rostral cornu of the thyroid cartilage

Articulation with the thyrohyoid bone.

239

Caudal cornu of the thyroid cartilage

Articulation with the caudal aspect of the cricoid cartilage

240

Caudal thyroid incisure

Notch on the ventral side of the thyroid cartilage that holds the cricothyroid ligament.

241

Cricothyroid ligament

Connects the caudal border of the thyroid cartilage to the cranial border of the cricoid cartilage.

242

Cricoid cartilage

Unpaired. A complete ring on the ventral aspect of the larynx. Has a lamina (wide dorsal plate) and a narrow ventral arch. Has a caudolateral facet for articulation with the thyroid cartilage and a craniolateral facet for articulation with the with corniculate process of the arytenoid cartilage.

243

Arytenoid cartilage

Paired. Mainly within the cricoid cartilage.

244

Muscular process of the arytenoid cartilage

Lateral. Attaches to laryngeal musculature.

245

Vocal process of the arytenoid cartilage

Ventral. Attaches to the vocal fold.

246

Corniculate process of the arytenoid cartilage

Dorsal, articulates with the cricoid cartilage.

247

Cuneiform process of the arytenoid cartilage

Cranial. Attachement for the vestibular fold.

248

Vestibular fold

Attached between the cuneiform process of the arytenoid cartilage and the thyroid cartilage. Rostral fold of the laryngeal ventricle.

249

Vocal fold

Attached between the vocal process of the arytenoid cartilage and the midventral part of the thyroid cartilage. Caudal fold of the laryngeal ventricle.

250

Laryngeal ventricle

Diverticulum of the laryngeal mucosa bounded by the vocal and vestibular folds. Important in phonation.

251

Pharynx

Open spaces formed in the caudal part of the head from nose and mouth to larynx.

252

Larynx

Structure formed by the four laryngeal cartilages.

253

Glottis

Structure formed by the vocal folds, vocal processes of the arytenoid cartilages, and the rima glottidis.

254

Rima glottidis

Narrow passageway through the glottis. Size and shape modulated by muscular activity.

255

Cricothyroid muscle

Lies ventral to the insertion of the sternothyroideus over the cricoid cartilage and trachea. Indirectly tenses the vocal cords (increases pitch) by drawing the ventral parts of the cricoid and thyroid cartilages together.
Innervated by the cranial laryngeal nerve, a branch of the vagus.
Only laryngeal muscle seen best on the lateral side of the head.

256

Cricoarytenoideus dorsalis

Dorsolateral surface of the cricoid to the muscular process of the arytenoid cartilage. Rotates the arytenoid so that the vocal process moves laterally and opens the glottis. This is accomplished by pulling the muscular process caudomedially. Very important during heavy breathing.
Innervated by the caudal laryngeal nerve (off the recurrent laryngeal n.)
Dysfunction can cause exercise intolerance, "roaring," laryngeal paralysis.

257

Cricoarytenoideus lateralis

Lateral surface of the cricoid cartilage to the muscular process of the arytenoid cartilage between the cricoarytenoidus dorsalis and the vocalis. Acts to close the glottis by pulling the muscular process ventrally and thus moving the vocal process medially.
Innervated by the caudal laryngeal nerve (off the recurrent laryngeal n.)
Disfunction causes increased likelihood of coughing/gagging/choking or aspiration pneumonia.

258

Thyroarytenoideus

Gives rise to the vocals medially and the ventricular rostrally. Internal midline of the thyroid cartilage to arytenoid cartilage. Relaxes the vocal fold (deepens pitch) and constricts the glottis.
Innervated by the caudal laryngeal nerve (off the recurrent laryngeal n.)

259

Vocalis

Medial division of the thyroarytenoideus, from internal midline of the thyroid cartilage to vocal process of the arytenoid cartilage.

260

Vocal ligament

Attached to the rostral border of the vocalis to attach it to the vocal process of the arytenoid cartilage.

261

Laryngeal muscles (4)

Cricothyroideus
Cricoarytenoideus dorsalis
Cricoarytenoideus lateralis
Thryoartenoideus

262

Auricular cartilage

aka pinna
One cartilage that is funnel shaped and forms the entirety of the external ear.

263

Tragus

Rostral boundary of the ear canal, think quadrangular plate.

264

Marginal cutaneous sac

aka cutaneous marginal pouch
Indentation/incisure at the lateral portion of the helix of the pinna.

265

Annular cartilage

Circular ring of cartilage that connects the auricular cartilage to the external acoustic meatus, helping form the ear canal.

266

Temporalis muscle

Attachments: Temporal fossa to coronoid process of the mandible.
Action: Close the jaw
Innervation: Mandibular branch of the trigeminal nerve (CN V)

267

Masseter muscle

Attachments: Zygomatic arch and masseteric fossa on the ventrolateral surface of the mandible. Fibers blend with the fibers of the temporals muscle in deep portion. Covered by a large aponeurosis.
Action: Close the jaw
Innervation: Mandibular branch of the trigeminal nerve (CN V)

268

Zygomatic salivary gland

Found directly ventral to the eye underneath the zygomatic arch. Gland opens into the vestibule by one main and several minor ducts lateral to the last superior molar tooth.

269

Medial and lateral pterygoid muscles

Hard to distinguish from one another - medial pterygoid is most of the muscle mass while lateral pterygoid is smaller.
Attachments: pterygopalatine fossa to medial surface and caudal margin of the ramus of the mandible and the angular process of the mandible. Can be felt from the medial side under the oropharynx.
Action: Close the jaw
Innervation: Mandibular branch of the trigeminal nerve (CN V)

270

Digastricus

Origin found under the mandibular and parotid salivary glands.
Attachments: paracondylar process of the occiptal bone to body of the mandible.
Action: Open the jaw
Rostral portion innervation: Mandibular branch of the trigeminal nerve (CN V)
Caudal portion innervation: Facial nerve (CN VII)
Rostral separated from caudal portion by a tendinous intersection that crosses the muscle belly.

271

Styloglossus

Attachments: Stylohyoid bone rostroventral to the palatine tonsil and inserts in the middle of the tongue.
Action: Retract and elevate the tongue.
Innervation: Hypoglossal nerve (CN XII)

272

Hyoglossus

Attachments: Thyrohyoid and basohyoid bones to the root of the tongue.
Action: Retract and depress the tongue.
Innervation: Hypoglossal nerve (CN XII)

273

Genioglossus

Attachments: Intermandibular articulation and joins its fellow on the median plane. Found on the medial side inside the tongue.
Action: Caudal fibers protrude the tongue and its rostral ones retract the apex.
Innervation: Hypoglossal nerve (CN XII)

274

Sternohyoideus

Attachments: Sternum and first costal cartilage to the basiohyoid bone.
Action: Draw the larynx caudally.
Innervation: Hypoglossal nerve (CN XII) and ventral branches of cervical spinal nerves.

275

Thyrohyoideus

Attachments: Short muscle rostral to the origin of the sternothyroideus. Thyroid cartilage of the larynx to thyrohyoid bone.
Innervation: Hypoglossal nerve (CN XII) and ventarl branches of the cervical spinal nerves.

276

Mylohyoideus

Attachments: Transverse fibers between the base of the mandibles from the medial surface of the body of the mandible to its fellow muscle on the midventral raphe. Inserts caudally on the basihyoid.
Action: Forms a sling that aids in the support of the tongue.
Innervation: Mandibular branch of the trigeminal nerve (CN V)

277

Geniohyoideus

Attachments: Lies deep to the mylohyoid. Arises at the intermandibular articulation and inserts on the basiohyoid.
Action: Draws the hyoid apparatus and larynx rostrally.
Innervation: Hypoglossal nerve (CN XII)

278

Name the arteries (in order) that supply the distal part of the hind limb

External iliac artery -> femoral a. -> popliteal a. -> cranial tibial -> dorsal pedal -> perforating branch of the arcuate artery.

279

What two main arteries supply the proximal part of the hind limb?

External Iliac artery and Internal Iliac artery

280

What two main arteries supply the hind paw?

Cranial tibial and saphenous arteries.

281

Which is larger, the perforating or arcuate artery of the hind paw?

Perforating artery.

282

What cranial nerves comprise the part of the lumbosacral plexus that innervates the hindlimb?

L4-S3

283

What nerve innervates the hamstrings?

Sciatic nerve
(Hamstrings = biceps femoris, semimembranosus, semitendinosus)

284

What nerve innervates the external anal sphincter? What may cause this nerve to stop working and what will happen if this occurs?

Caudal rectal nerve (off of the pudendal nerve)
Perianal hernia, chronic anal sac disease or pelvic damage can cause nerve damage, and loss of this can cause loss of voluntary control of defecation.

285

What nerve innervates the extensors of the hock/flexors of the digits?

Tibial nerve

286

What does damage to the tibial nerve look like in the patient?

Sinking of the hock because it cannot be kept in extension.

287

What nerve innervates the flexors of the hock/extensors of the digits?

Deep peroneal/deep fibular nerve

288

What nerve innervates the extensors of the stifle?

Femoral nerve

289

What nerve innervates the adductors of the hindlimb?

Obturator nerve
Also prevents abduction
Loss is most obvious on a slippery surface.

290

At what vertebrae does the spinal cord end?

Around L6/L7 between the wings of the ilium, then continues as the caudal equina running through the verterbral canal.

291

Where do the nerves of the caudal equina exit the vertebral column?

At the vertebrae that they are named for, even if their origin is much more cranial within the spinal cord.

292

What is the importance of the many foramina of the skull?

Blood must get in
Nerves must come out

293

Which cranial nerves have parasympathetic components?

III, VII, IX, and X only

294

What are the names of the two types of dental nomenclature?

Anatomical shorthand system
Modified Triadan system (more common in clinics)

295

What is the dental formula of the adult feline?

3/3 I, 1/1 C, 3/2 P, 1/1 M

296

What is the dental formula of the kitten?

3/3 I , 1/1C, 3/2 P

297

What are the quadrants of the modified Triadan system?

Moves in a clockwise (from the vet's perspective) direction around the mouth.
1 = Upper right
2= Upper left
3= Lower left
4= Lower right

298

Describe how the anatomical shorthand system works to identify a specific tooth

Type of tooth is ID'd by I, C, P, or M
Number is placed on top or bottom and on either the right or left to indicate the position of the tooth.

299

What is the pathway of the sympathetic innervation of the head?

Approx T1 -> cervicothoracic ganglion -> middle cervical ganglion -> vagosympathetic trunk -> cranial cervical ganglion -> smooth muscle of the pupil and blood vessels, sweat, and mucosal glands of the head.

300

Why is the visualization of the eardrum in the dog so difficult?

Ear canal turns over 90 degrees from the external ear to the tympanic bulla. Have to point the otoscope medially.

301

Where is a nasogastric tube passed?

Through the common nasal meatus which is very simple rostrally and more complex/smaller caudally.

302

Why do we get stuffy noses with a cold?

The caudal turbinates have incredibly complex blood sinuses. An increase in blood flow from inflammation during a viral infection will cause a restriction in space = part of a stuffy nose.

303

Why do dogs get watery eyes with nasal swelling?

The nasolacrimal canal is very small in the dog so nasal or ocular swelling will usually occlude the canal. This will mean that tears will spill out of the eye rather than moving into the nasal cavity to evaporate.

304

What are the general actions the pharyngeal musculature?

Relaxation: increase the size of the lumen
Contraction: decrease the size of the lumen
Important in both swallowing and vocalization.

305

Where does the soft palate sit relative to the epiglottis in the living dog?

Soft palate is generally ventral to the epiglottis. (In fixed specimens they are usually contacting one another). Held in place by musculature.

306

What causes reverse sneezing?

In brachyocephalic dogs the soft palate is disproportionately long compared to the face. It can then become flipped over (becomes dorsal to) the larynx causing sneezing/coughing/gagging as the dog tries to fix the situation.

307

What must happen in order for the dog to pant?

Must dilate the pharynx to allow mouth breathing and so completely relax the pharyngeal muscles.

308

What types of joints form between the laryngeal cartilages and the hyoid bones?

Synovial joints

309

Wattles

Cheek fleshy material of the chicken. Color can be used to judge overall health (pink vs. pale or jaundiced).

310

Comb points

Fleshy material on the top of the head of the chicken. Color can be used to judge health like the wattles.

311

Pterylae

Feathered portion of bird skin

312

Apterylae

Non-feathered portion of bird skin (feather tracts)

313

What kind of keratin is found in birds/reptiles?

Beta-keratin

314

Patagium

The skin that stretches between the humerus and radius/ulna in the wing of the bird.

315

Urophygeal gland

Oil gland on the rump that helps birds with preening and waterproofing.

316

Are cream or brown feathers darker?

Darker feathers are stronger due to the melanins in the tissue.

317

What are the three elements that cause feather coloring?

Melanins, carotenoids, and porphyrins.

318

What are iridescent feathers an example of?

Structural colors.

319

Strut framework

Element of avian hollow bones that keeps them strong as the bone becomes stronger for flight.

320

Medullary bone

Laid down as PULLET in young female birds. Still hollow but in the larger bones as a calcium for females during egg production. Can eventually become depleted leading to soft-shelled eggs.

321

How many cervical vertebrae do birds have?

Variable number - swans have up to 22.

322

What 6 specialized reduced bones do birds have?

Keel
Synsacrum
Carpometacarpus
Tibiotarsus
Tarsometatarsus
Reduced digits

323

What is the movement of a bird's maxillary bone called?

Cranial kinesis

324

Furcula

aka the wishbone
Fused clavicles of birds

325

Avian pectoral muscles

For a down-stroke in flight.
Superficial to supracoracoideus.
Attachments: Keel and ventral humerus (cranial to scapula).

326

Avian Supracoracoideus

For an up-stroke in flight.
Deep to pectorals
Attachments: keel and dorsal humerus (caudal to scapula).

327

Why don't birds fall off their perches as they sleep?

The tendons of the hock flexors are very long so as the bird kneels they tighten and flex the toes. This also helps them when carrying food after hunting.

328

What is the stroke pattern of avian respiration?

1. To abdominal air sacs
2. Through rigid lungs
3. To cervical air sacs
4. Out through trachea

329

What three holes do you find in the oral cavity?

Choana (top of the bill)
Glottis (bottom)
Esophagus

330

Bird mechanical papillae

Cause the food to move down the esophagus rather than back up it.

331

What causes the noises caused by very noisy birds?

Highly elongated trachea

332

What allows birds to sing dual-tone songs?

The syrinx, which allows different notes to be produced at the same times.

333

How does the avian heart deviate from the mammalian heart?

Much thinner R ventricle
Very pointed heart
R atrioventricular valve is muscular rather than fibrous and so can be affected by myocarditis.

334

What is the shell gland of the bird analogous too?

The uterus

335

What veins are accessible for venipuncture in the bird

R. jugular vein
Metatarsal vein
Cutaneous ulnar or Basilic vein

336

What organ is found in young birds and then fades in the adult?

The Bursa of Fabricius where B-lymphocytes develop. Found near the cloaca.

337

What accounts for the variability of normal bird stools?

Cecal droppings
Paired and very long on either side of the colon.

338

What organ in mammals is missing in avians?

The urinary bladder
Urates directly into the GI tract.

339

What is the problem with giving IM injections into the leg of a bird?

Birds have a portal renal system as well as a hepatic renal system and so drugs are often cleared before becoming systematic. This is why the pectoral muscles are generally used for IM injection in birds.

340

Periorbita

The cone-shaped connective tissue that encloses the eyeball and its muscles, vessels, and nerves. Continuous with the periosteum of the orbit and the face and continuous with the dura intracranially.

341

Lacrimal gland

Small flat gland lying deep (medial) to the orbital ligament.. Creates 2/3 of the aqueous layer of the tear film.

342

Levator palpebrae superioris

Narrow, superficial muscle that runs from the apex of the orbit and over the dorsal rectus and then becomes a flat tendon in the upper eyelid. Innervated by the oculomotor nerve (CN III).

343

How many extrinsic muscles of the eye?

7
Retractor bulbi
Two obliquus muscles (dorsal/ventral)
Four rectus muscles (dorsal/ventral/medial/lateral)

344

Describe the arrangement of the extrinsic muscles of the eye.

4 fascicles of the retractor bulbi in the center
Surrounded by the four rectus muscles
Obliquus muscles attach at the sclera over the ventral and dorsal rectus muscles.

345

What extrinsic muscles of the eye does CN III innervate?

Oculomotor:
Dorsal rectus
Medial rectus
Ventral rectus
Ventral oblique

346

What extrinsic muscles of the eye does CN VI innervate?

Abducens:
Retractor bulbi
lateral rectus

347

What extrinsic muscles of the eye does CN IV innervate?

Trochlear:
Dorsal oblique

348

Trochlea

Cartilagenous plaque attached at the level of the medial angle of they eye to the wall of the orbit. Holds the tendon of the dorsal oblique muscle.

349

Superficial gland of the third eyelid

At the bottom of the third eyelid. Produces 1/3 of the aqueous layer of the tear film. Do not confuse with the lymphatic nodules that are on the visceral side of the third eyelid.

350

External fibrous coat of the eye

Composed of the cornea, sclera, and limbus.
Complete
Derived from neural crest cells.

351

Cornea

Anterior 1/4 of the eye. Clear portion through which the iris and pupil are seen.

352

Sclera

Posterior 3/4 of the eye. "White" of the eye. Covered by the bulbar conjunctiva anteriorly. Attachments of the extrinsic muscles of the eye, penetration of vessels, and exit of the optic nerve posteriorly.

353

Limbus

The slightly thickened joining point of the sclera and the cornea.

354

Middle vascular coat of the eye

Aka uvea.
The iris, choroid, and ciliary body.
Incomplete.
Derived from neural crest cells.

355

Iris

Pigmented diaphragm surrounding the pupil. Has both circular and radial smooth muscle.

356

Pupil

Opening in the center of the iris.

357

Choroid

Posterior portion of the vascular coat firmly attached to the sclera (middle coat of the fundus). Continuous with the ciliary body anteriorly. Consists of the tapetum lucid and the nontapetal area (nontapetal nigrum).
Provides the majority of the blood flow to the globe.

358

Ora serrata

Junction of the choroid and the ciliary body. Usually seen as an undulating line in the retina.

359

Fundus of the eye

Posterior or deep portion of the eyeball that is seen with the ophthalmoscope during an eye exam.

360

Tapetum lucidum

Specialized layer of cells in the choroid that is multicolored and reflects light rays. Reflection causes light rays to trigger the rods and cones of the retina twice and so may be important for vision in low light.

361

Ciliary body

Between the iris and the choroid. Numerous muscle bundles that function in the regulation of the shape of lens.

362

Ciliary processes

From the ciliary body. Surround but do not attach to the lens of the eye. Consist of several hundred pigmented folds (help give the iris its color) that alternate in length and enlarge as they approach the lens. Contraction of the processes pulls on zonular fibers and makes the lens more spherical to accommodate for near vision.

363

Zonule

The suspensory apparatus of the lens. Composed of numerous zonular fibers.

364

Zonular fibers

Fine strands that pass from the ora serrata along the ciliary processes and attach to the equator of the lens. Contraction of the ciliary processes pulls on zonular fibers and makes the lens more spherical to accommodate for near vision.

365

Lens

Transparent and elastic roundish structure through which light passes.

366

Chambers of the eye

Anterior chamber: between the cornea and the iris, filled with aqueous humor.
Posterior chamber: between the iris and the lens, filled with aqueous humor.
Vitreous chamber: posterior to the lens, filled with vitreous humor.

367

Vitreous humor

Jelly-like proteinous substances which fills the vitreous chamber. Used often in necropsies because there may be electrolytes remaining in this, often a sterile chamber.

368

Aqueous humor

Continually produced by the the ciliary epithelium that covers the ciliary processes. Circulates through the posterior chamber and then into the anterior chambers. Then drained through the trabecular meshwork at the iridocorneal angle into the venous scleral sinus.

369

Iridocorneal angle

Angle that contains a trabecular meshwork through which the aqueous humor drains.

370

Scleral sinus

Venous sinus into which the aqueous humor drains.

371

Pectinate ligament

The meshwork in the iridocorneal angle.
Holes in the meshwork are called the spaces of Fontana.

372

What causes glaucoma?

Failure in the drainage of the aqueous humor of the eye, especially if the meshwork (spaces of Fontana) of the pectinate ligament becomes blocked.

373

Internal (nervous) coat of the eye

Retina and associated vessels and nerves.
Incomplete
Formed from a direct outgrowth of the brain.

374

Retina

Pars optica retinae
Pars ciliaris retinae
Pars iridica retinae

375

Pars optica retinae

Covers the fundus. Portion of the retina that contains the light sensitive rods and cones, the bipolar cells, and the ganglion cells. Appears as a gray-white layer that peels away from the choroid in the preserved specimen.

376

Pars ciliaris retinae

Non-light receptive portion of the retina over the ciliary body. Two layers thick and forms the blood-aqueous barrier through which aqueous fluid is secreted into the posterior chamber.

377

Pars iridica retinae

Portion of the retina over the posterior section of the iris. Double cell layer of the retina with one layer consisting of pigment cells (help give iris its color) and a second layer of myoepithelial cells.

378

Dilator pupillae

Myoepithelial cells of the pars iridica retinae.

379

Optic disk

Point at which the the optic nerves enters the posterior part of the globe. Many retinal vessels also enter here. Near or slightly inferior to the tapetum lucidum.

380

External jugular vein

Formed by the anastamosis of the linguofacial vein and the and the maxillary veins, with the mandibular salivary gland between the two veins.

381

Lingual vein

First large tributary that enters the linguofacial vein. Different radiating veins drain blood from the tongue, laryrnx, and pharynx.

382

Liguofacial vein

Tributary of the cephalic vein.
Has several small mandibular lymph nodes along it that are rostroventral to the mandibular salivary gland.

383

Facial vein

Other tributary of the liguofacial vein. Drains the dorsal surface of the muzzle
Branches: dorsal nasal
angularis oculi

384

Dorsal nasal vein

Branch of the facial vein that runs caudally from the nares.

385

Angularis oculi vein

Branch of the facial vein that runs rostrally from the medial aspect of the orbit where it is continuous with the ophthalmic plexus in the periorbita.

386

Deep facial vein

Another communication between the ophthalmic plexus and the facial vein. Ventral to the zygomatic bone.

387

Maxillary vein

Second component of the external jugular vein.
Drains the ear, orbit, palate, nasal cavity, cheek, mandible, and cranial cavity.

388

Facial nerve

CN VII
GSE: Innervates all of the superficial muscle of the head and face as well as the caudal belly of the digastricus and the platysma of the neck, eyelids.
SVA: Carries taste sensation from the rostral 2/3 of the tongue
GVE: parasympathetic input to the lacrimal, sublingual, and mandibular salivary glands as well as the glands of the nasal and oral cavity
Enters the petrosal part of the temporal bone through the internal acoustic meatus and them exits the eli; at the stylomastoid foramen and breaks into branches.
Major branches: auriculopalpebral, dorsal an ventral buccal branches.

389

Auriculopalebral nerve

Arises from the facial nerve ventral to the external acoustic meatus.

390

Rostral auricular branches of the auriculopalebral nerve

Braches that run through the parotid gland and are distributed to the rostral auricular muscles.

391

Palpebral branches of the auriculopalebral nerve

Branch that supplies the orbicular oculi (responsible for closing the eyelid).

392

Buccal branches of the facial nerve

Branches that run across the masseter muscle to the cheek, superior and inferior lips, and lateral surface of the nose. Ventral and dorsal branches, named in relation to the parotid duct.

393

Auriculotemporal nerve

Branch of the mandibular nerve (from CN V trigeminal) from between the caudal border of the masseter and external acoustic meatus.
Sensory branches to the skin of the external ear, temporal, zygomatic, and masseteric regions.

394

Thyroid gland

Two lobes (maybe connected by an isthmus) lateral to the first five rings of the trachea.
Supplied by the caudal thyroid artery and the cranial thyroid artery.

395

External parathyroid gland

Small lightly colored spherical body.
Most commonly found in the fascia near the cranial pole of the thyroid gland.
Supplied by the cranial thyroid artery.

396

Internal parathyroid gland

Small lightly colored spherical body.
Usually within the capsule of the thyroid on the medial side of the structure.
Supplied by the cranial thyroid artery.

397

Cervical portion of the esophagus

From the laryngopharynx (starting at the pharyngoesophageal limen) to the thoracic inlet.

398

Tracheal cartilages

Approximately 35 in the dog, C-shaped, open dorsally and this opening is covered by the trachealis muscle.

399

Common carotid artery

Within the carotid sheath. Branches of this artery will supply all the major structures of the head.

400

Caudal thyroid artery

Variable origin from a major arterial vessel at the thoracic inlet. Runs cranially on the trachea to the caudal pole of the thyroid gland.
Supplies: trachea, esophagus, and thyroid gland.

401

Cranial thyroid artery

From common carotid artery. Runs ventrocaudally.
Supplies thyroid and parathyroid glands, pharyngeal muscles, laryngeal muscles and mucosa, cervical parts of the trachea and esophagus, and portions of the sternocephalicus and mastoid part of the cleidocephalicus.

402

Medial reteropharyngeal lymph node

Large lymph node near the larynx.
Drains the tonsils, tongue, nasal cavity, pharynx, salivary glands, external ear, larynx, and the esophagus.
Tracheal trunk on each side arises from this lymph node.

403

Internal carotid artery

Runs more cranially than the external carotid artery.
No branches off this artery but runs into the carotid canal within the tympanooccipital fissure.
Forms the cerebral arterial circle that supplies the brain.

404

Carotid sinus

Sac-like structure formed by the branching point of the internal and external carotid arteries. Baroreceptor. The carotid body (chemoreceptor) lies within the carotid sinus.

405

External carotid artery

Runs more caudally than the internal carotid artery.
Numerous branches supply other structures of the head:

Terminates by branching into the superficial temporal artery and the maxillary artery just rostrally to the auricular cartilage.

406

Superficial temporal artery

The smaller terminal branch of the external carotid artery.
Supplies the parotid gland, the masseter (via the masseteric artery which can be mistaken for the maxillary), the temporal muscle, the rostral auricular muscles, and the eyelids.

407

Maxillary artery

The larger terminal branch of the external carotid artery.
Disappears deep to the masseter muscle.
Associated with a number of cranial nerves.
Courses towards the alar canal.
Branches:
(caudal deep temporal artery, middle meningial artery, and external ophthalmic artery)
Minor palatine artery
Descending palatine artery
Terminates as the infraorbital artery.

408

Occipital artery

Leaves the external carotid cranially just after the internal carotid.
Supplies the muscles on the caudal aspect of the skull and the meninges.

409

Cranial laryngeal artery

Small ventral branch of the external carotid with a sharp curve that supplies the sternomastoideus, pharyngeal muscles, and laryngeal muscles and mucosa.

410

Lingual artery

Large ventral branch of the external carotid that courses rostrally to supply the tonsil and the tongue.
Closely associated with the hypoglossal nerve.

411

Facial artery

Large rostroventral branch of the external carotid that leaves just rostral to the lingual artery.
Supplies the lips and nose.
The sublingual artery branches off this artery.

412

Sublingual artery

Branch off of the facial artery that supplies the digastric muscle and the tongue.
Closely associated with the mylohyoid nerve.

413

Caudal auricular artery

Dorsal branch off of the external carotid artery which generally arises under the base of the ear and parotid gland.
Lateral, intermediate, and medial branches that course distally on the convex surface of the external ear.

414

CN V Mandibular branch

Branch of the Trigeminal nerve
Leaves the skull through the oval foramen
Branches arise over the pterygoid muscles : pterygoid, deep temporal, and masseteric nerves that contain somatic motor neurons (GSEs) to innervate the mm. of mastication.
To mylohyoid nerve, inferior alveolar nerve, lingual nerve, and auriculotemporal nerve.

415

Lingual nerve

Sensory
Largest and most rostral branch of the mandibular nerve
Somatosensory to the rostral 2/3 of the tongue (GSA). Does not provide any taste sensation.

416

Inferior alveolar nerve

Middle branches of the mandibular nerve.
Enters the mandibular foramen on the medial side of the ramus of the mandible and then runs through the mandibular canal to supply sensory nerves to the teeth.
Mental branches from the mental foramina are terminal branches of this nerve.
Runs with the inferior alveolar artery

417

Mylohyoid nerve

Most caudal branch of the mandibular nerve.
Both motor and sensory. Runs around the caudal aspect of the mandible to the medial side and is motor to the digastric / mylohyoid and sensory to the skin between the mandibles.

418

Auriculotemporal nerve

Sensory
Leavers the mandibular nerve at the oval foramen and courses caudally.
Emerges between the base of the auricular cartilage and the masseter muscle.
Supplies the ear and the lateral aspect of the head.

419

External ethmoidal artery

Branch of the maxillary artery (from the external ophthalmic artery that supplies the eye).
Passes and turns sharply dorsal to the extrinsic musculature of the eye, then enters an ethmoidal foramen into the cranial cavity and passes through the cribriform plate to supply the ethmoid labyrinth and nasal septum.

420

Descending palatine artery

Common trunk from the maxillary artery that will branch into the major palatine artery (caudal) and the sphenopalantine (cranial).

421

Minor palatine artery

Very small ventral branch off the maxillary artery just caudal to the descending palatine artery.
Distributed to the hard and soft palates.
Often run into during bleeds in dental work.

422

Major palatine artery

From the descending palatine artery - caudal branch.
Enters the caudal palatine foramen and thought the major palatine canal to supply the hard palate.

423

Sphenopalatine artery

From the descending palatine artery - cranial branch.
Through the sphenopalatine foramen to supply the interior of the nasal cavity.

424

Infraorbital artery

The continuation of the maxillary artery.
Supplies the malar a. to the eyelids, dental branches to the caudal cheek teeth, then runs through the maxillary foramen and supplies more dental branches to supply the premolars, canines, and incisors.
Terminates as the lateral and rostral dorsal nasal arteries that supply the nose and upper lip.

425

Inferior alveolar artery

Runs with the inferior alveolar nerve
Supplies the roots of the teeth in the lower jaw.
Branches = mental branches that supply the skin.

426

Olfactory nerve

CN I
SVA: sensory from the olfactory epithelium in both the nasal cavity and vomeronasal organ. In reality numerous olfactory axons passing through the olfactory foramina.

427

Optic nerve

CN II
SSA: from the retina to the CNS. Enters the skull via the optic canal in the presphenoid bone. Lies medial to the lateral rectus and fasicle of the retractor bulbi. Covered here by an extension of the meninges.

428

Oculomotor nerve

CN III
GSE: Innervation of the structures of the orbit/adnexa including the ventral, medial, and dorsal recti, the ventral oblique, and the levator palpebrae superioris muscle.
GVE Parasympathetic: innervation to the ciliary muscle and sphincter (constrictor) pupillae muscle.
Exits the skull via the orbital fissure.
Can be seen as the much smaller nerve ventrolateral to the optic nerve.

429

Ciliary ganglion

VERY small round expansion of the distal trunk of the oculomotor nerve. Collection of postganglionic parasympathetic cell bodies supplying the sphincter pupillae and ciliary muscles. One of the few parasympathetic ganglia that can be seen outside of the tissue innervated, and functions to regulate the size of the pupil.

430

Trochlear nerve

CN IV
GSE: to dorsal oblique muscle (caudal belly).
Travels through the orbital fissure.
Cannot be seen in our dissections.

431

Trigeminal nerve

CN V
GSA from all regions of the face, rostral part of the auricle, rostral portion of the tongue, and external acoustic meatus.
Ophthalmic, mandibular, and maxillary divisions.

432

Ophthalmic nerve

CN V branch
Cannot see on our specimens
Through the orbital fissure
Sensory information from the region of the forehead, the medial regions of the superior and inferior eyelids, the cornea and the rest of the globe, some of the nasal mucosa. The branches divide within the periorbita.
Branches are the frontal, nasociliary, and lacrimal nerves.

433

Frontal nerve

A branch off of the ophthalmic nerve that travels rostrally with the infratrochlear nerve. Innervates the medial surface of the eyelids.

434

Infratrochlear nerve

A branch off of the ophthalmic nerve nerve that travels rostrally with the frontal nerve. Innervates the medial surface of the eyelids.

435

Ethmoidal nerve

Branch of the ophthalmic nerve that passes through the ethmoidal foramen with the ethmoidal artery and through the cribriform plate to innervate the nasal muscosa and skin of the nose.

436

Maxillary nerve

CN V branch
Travels through the round foramen and then the rostral alar foramen, accompanied by the maxillary artery.
Sensory from the nose, upper lip, lateral regions of the eyelids, superior dental arch, some of the nasal cavity, the hard and soft palates, and the lateral region of the face over the maxilla and zygomatic bones.

437

Zygomatic nerve

Branch of the maxillary nerve. Enters the periorbita and divides into two branches that pass rostrally on the inner surface of the lateral part to innervate the lacrimal gland and lateral portions of the eyelids.

438

Pteryopalatine ganglion

Flat neuronal cluster on the dorsolateral surface of the medial pterygoid cluster next to the pteryopalatine nerve.
Collection of postganglionic parasympathetic cell bodies of CN VII whose axons travel with branches of the maxillary nerve to innervate the lacrimal glands and the mucosa of the nasal cavity and palate.

439

Pteryopalatine nerve

Branch of the maxillary nerve
Common nerve trunk crossing the surface of the medial pterygoid in the pteryopalatine fossa next to the pteryopalatine ganglion.
Formed by the palatine nerves and the caudal nasal nerves

440

Minor palatine nerve

Forms part of the pterypalatine nerve and ganglion. Innervates the palate.

441

Major palatine nerve

Forms part of the pterypalatine nerve and ganglion.
Innervates the palate.

442

Caudal nasal nerves

Forms part of the pterypalatine nerve and ganglion.
Innervates the nasal mucosa.

443

Infraorbital nerve

Branch of the maxillary nerve
Large rostral continuation of the nerve that passes through the maxillary foramen and the infraorbital foramen with the infraorbital artery.
Innervates the skin and adjacent structures of the superior lip and nose.
Branches into superior alveolar.

444

Superior alveolar nerves/branches

Branches of the infraorbital nerve that stay within the maxilla and supply the superior cheek teeth.

445

Abducent nerve

CN VI
GSE: lateral rectus and retractor bulbi
Emerges from the orbital fissure
Can see well on the medial side of the lateral rectus.

446

Vestibulocochlear nerve

CN VIII
SSA related to hearing and balance from the inner ear to the brainstem via the internal acoustic meatus

447

Cranial cervical ganglion

Cranial terminal point of the vagosympathetic trunk and most cranial sympathetic ganglion.
Vagus nerve and many sympathetic and motor axons innervating the pharynx branch off here. Nerves also distributed to the vessels, glands, and smooth muscles of the head.

448

Glossopharyngeal nerve

CN IX
Divides into pharyngeal and lingual branches
SVA - taste from the caudal 1/3 of the tongue
GVA - from caudal 1/3 of the tongue, pharynx, and carotid sinus.
GVE - parotid and zygomatic salivary glands
GSE - pharyngeal muscles
Use the external carotid artery and the cranial cervical ganglion as landmarks to ID the glossopharyngeal which is between them.
Exits via the tympanooccipital fissure and jugular foramen

449

Vagus nerve

CN X
GVA - abdominal and thoracic viscera
SVA - taste information from around the epiglottis
GVE - parasympathetic innervation to thoracic and abdominal viscera
GSE - skeletal muscle of the pharynx, esophagus, and larynx
Exits the skull via the tympanooccipital fissure with cranial nerves IX and XI.

450

Proximal ganglion of the vagus

Lies in the jugular foramen and cannot be seen in our specimen.

451

Distal ganglion of the vagus

Enlargement of the vagus near the split of the vagosympathetic trunk, outside the tympanooccipital fissure. Collection of visceral afferent cell bodies similar to a dorsal root ganglion adjacent to the spinal cord.

452

Pharyngeal plexus

The network of branches from the glossopharyngeal nerve that run to the pharynx and the tongue along with fibers from the vagus and postganglionic sympathetic axons. Also innervates the cranial esophagus.

453

Cranial laryngeal nerve

Found near the distal ganglion of the vagus and courses along the lateral border of the larynx. Dives between pharyngeal muscles to innervate the cricothyroid muscle and some of the laryngeal mucosa.

454

Accessory nerve

CN XI
GSE - sternocephalicus, brachiocephalicus, omomtransversarius, and trapezius, and also helps to contribute to the innervation of the laryngeal muscles (by joining with the vagus near the jugular foramen.
Exits via the tympanooccipital fissure and jugular foramen.

455

Hypoglossal nerve

CN XII
GSE - muscles of the tongue (extrinsic and intrinsic)
Exits the skull via the hypoglossal canal
Can be seen most readily near the hyoglossus but can also be found lateral to the external carotid artery.
Closely associated with the lingual artery.

456

Vagosympathetic trunk

Joins with the vagus at the cranial cervical ganglion. Cranial cervical ganglion gives off many axons to the walls of the pharynx.

457

Olfactory foramina

Holes in the cribriform plate through with fibers of the olfactory nerves pass.

458

Caudal laryngeal nerve

The continuation of the recurrent laryngeal nerve that runs along the trachea and dives into the caudal part of the larynx.
Supplies motor to all of the laryngeal muscle except for the cricothyroideus.

459

How are the cranial nerves named?

Roman numerals indicate the order in which they arise from the brain in the rostrocaudal direction.
Names are descriptive

460

Ciliary nerves

Branches off the ophthalmic nerve that follow the optic nerve and innervate the eyeball.

461

Ansa cervicalis

Loop that leaves the hypoglossal were to join the first cervical spinal nerve before rejoining the hypoglossal nerve in the region of the hyoid.

462

What type of renal system do avians have?

Urecotelic (can produce uric acid or urates)

463

Sclerotic ring

Bony ring in the avian orbit to support the more compressed eye

464

Pecten

Rectangular structure in the avian eye thought to provide nutrition to the eye

465

Columella

Only ear ossicle of the bird

466

Egg yolk peritonitis

Occurs if an ovum is passed from the ovary that is not caught by the infundibulum, large as it is.

467

Uncinate processes

Sharp processes off the avian ribs.

468

In what range can mammals see light? Birds?

Mammals: 400 - 700 nm
Birds: 300 - 700 nm

469

Adnexa

Structures around the globe both to move and support it.

470

Canthus (medial or lateral)

Another name for the medial/lateral commissures or angles of the eye.

471

What are the corresponding terms for the eye?
Rostral
Dorsal
Caudal
Ventral

Anterior
Superior
Posterior
Inferior

472

Equator of the eye

Circumference of the sclera cutting the globe into anterior and posterior halves. Where many extrinsic muscles of the globe attach.

473

What muscle opens the eyelids? What is it innervated by?

Levator palpebrae superioris
CN III

474

What muscle closes the eyelids? What is it innervated by?

Orbicularis oculi
CN VII

475

Describe the path of tear flow over the eye

1/3 of aqueous tears produced at the inferior gland of the 1/3 eyelid and 2/3 of aqueous tears produced at the superior/lateral lacrimal gland.
Tear film distributed over the eye by blinking
Move into the lacrimal puncta
Run through the lacrimal caniculi
The two caniculi meet at the lacrimal sac
Runs through the nasolacrimal duct to the ventral nasal meatus.

476

What is the cause of cherry eye? Treatment?

Inflammation of the lymphoid tissue of the third eyelid.
Can try to manage medically but most commonly just tack the eyelid down with suture.

477

How can you tell conjunctival vessels from scleral vessels?

Scleral vessels are fixed and don't move if prodded, while conjuctival vessels do. Can be important clinically.

478

What does the doctor look at during an eye exam?

Mostly examines the fundus of the eye
Looks for health of the vessels in the eye
Can observe the optic disc within the fundus

479

What developmental structure forms the lens of the eye?

Neural crest cells that form the lens placode.

480

What structure forms the optic stalk and cup of the developing eye?

Outgrowths of the optic vesicle of the primordial brain. These cause the lens placode to fold and bud off into the lens.

481

What is a reflex?

A programmed response to a stimulus.
Includes both an afferent and efferent arm.

482

What does a neurological exam entail?

Assessing of different reflexes as a way of locating a structural nerve lesion.

483

What is the simplest type of reflex arc?

A monosynaptic reflex arc in which the afferent neuron synapses directly onto the efferent neuron. This is only possible when both afferent and efferent neurons are associated with the same structure (such as a muscle in the patellar reflex). Generally, reflexes contain more synapses than this.

484

Panniculus reflex

Skin twitch reflex.
Afferents and efferents processed in the spinal cord and another signal is sent for conscious perception to the brain.

485

What might cause an increase in the panniculus reflex?

A lesion of the cervical spinal cord.
The conscious perception of the brain is usually somewhat inhibitive of the reflex. If it is not accessed, the reflex can appear to increase.

486

Which of the senses are visceral?

Taste and smell
Those that cannot be tuned in and out by conscious thought.

487

Which of the senses are somatic?

Vision and hearing (and touch)
Those that can be tuned out by conscious thought (or that are intimately associated with musculature)

488

How do you test CN I?

Test sense of smell
Make sure that whatever is being used does not provide mechanical stimulation of the nasal mucosa via movement of air or irritation.
At home, owner may see decrease in appetite or change in eating behavior.

489

What tests can be used to assess CN II?

Pupillary light reflex
Menace or startle response
Obstacle course
Visual tracking
If vision loss is gradual, deficits most often noticed when there is a sudden change in environment.

490

What tests can be used to assess CN III?

Pupillary light reflex
Eye movement
Relative position of the pupils in both eyes in rest and during tracking
Relative pupil diameter
Upper eyelid position

491

What is mydriasis and what innervates it?

Dilation of the pupil by the dilator pupillae muscle.
Radially arranged smooth muscle around the eye
Sympathetic input from T1-T3

492

What is miosis and what innervates it?

Construction of the pupil by the constrictor pupillae muscle.
Circularly arranged smooth muscle around the eye like a sphincter.
Parasympathetic input from CN III

493

What are the responses of the pupils called when testing the pupillary light reflex?

Direct response
Consensual response in the contralateral eye.

494

You shine a light in the right eye and neither pupil constricts. Which nerve is lesioned?

The right optic nerve.

495

You shine a light in the right eye and only the right pupil constricts. Which nerve is lesioned?

The left oculomotor nerve.

496

You shine a light in the right eye and only the left pupil constricts? Which nerve is lesioned?

The right oculomotor nerve.

497

You shine a light in the right eye and both pupils constrict. Which nerve is lesioned?

There may be no lesion, or there may be a lesion of the left optic nerve if you then shine the light into the left eye and see no pupil response in either pupil. To perform the PLR you always must look in both eyes.